Safety trailer hitch

ABSTRACT

A safety trailer hitch in which a ball is mounted on the towing vehicle and a ball clamping coupling is mounted on the trailing vehicle. A member carrying a finger is arranged on the towing vehicle to be positioned with the finger overlying the coupling to prevent the coupling from detaching from the ball even if unlocked. The finger is mounted to be swung out of the way as required to permit the coupling to be disconnected from the ball. In a modified form of the invention a yoke is mounted on the towing vehicle for swinging to a position overlying the coupling to prevent the coupling from being detached from the ball.

Kothmann 1 Sept. 1, W73

[ SAFETY TRAILER HITCH [76] Inventor: Gilbert C. Kothmann, PO. Box 680,

Mason, Tex. 76856 221 Filed: Nov. 19, 1971 211 App]. N6; 200,476

Related 0.8. Application Data [63] Continuation-impart of Ser. No.23,373, March 27,

1970, Pat. No. 3,677,564. I

Primary Examiner-Robert R1 Song Att0meyBerman, Davidson & Berman [57]ABSTRACT A safety trailer hitch in which a ball is mounted on the towingvehicle and a ball clamping coupling is mounted on the trailing vehicle.A member carrying a finger is arranged on the towing vehicle to bepositioned with the finger overlying the coupling to prevent thecoupling from detaching from the ball even if unlocked, The finger ismounted to be swung out of the way as required to permit the coupling tobe disconnected from the ball.

in a modified form of the invention a yoke is mounted on the towingvehicle for swinging to a position overlying the coupling to prevent thecoupling from being detached from the ball.

3 Claims, 5 Drawing Figures PAIENIEU SEP 1 a ma sum 2 or 2 SAFETYTRAILER HITCH CROSS REFERENCE TO RELATED APPLICATION This application isa continuation-in-part of my copending application Ser. No. 23,373,filed Mar. 27, 1970 entitled Safety Trailer Hitch", now US. Pat. No.3,677,564.

BACKGROUND OF THE INVENTION 1. Field of the Invention The presentinvention relates to safety trailer hitches of the type normally used totow boat trailers, utility trailers, camping trailers, and the like witha passenger automobile or light truck.

2. Description of the Prior Art In prior art devices it has been normalto use safety chains between the trailing and towing vehicles, tomaintain the alignment of the trailing vehicle with the towing vehicle,should the coupling become disconnected from the ball. A considerableamount of slack is required in the chains to permit the normal swivelingaction of the trailer and this slack creates problems when the hitchbreaks or becomes disconnected and the only connection between thetrailer and the towing vehicle is the chains. The trailer is thenpennitted to whip from side to side due to the slack in the chains andmany wrecks have been traced to this whipping action which caused thedriver of the towing vehicle to lose control of the car.

SUMMARY OF THE INVENTION The present invention includes a finger mountedon the towing vehicle and arranged to be releasably positioned tooverlie the trailer coupling to prevent it from being disengaged fromthe ball accidentally.

In a modified form of the invention a yoke is mounted on the towingvehicle and is arranged to swing to a position overlying the couplingand ball to prevent the coupling from being detached from the ballaccidentally.

The primary object of the invention is to provide a safety trailer hitchfor maintaining the safe coupiing of a trailer with its towing vehiclein the event the normal coupling becomes unlocked.

Other objects'and advantages will become apparent in the followingspecification when considered in light a of the attached drawings.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of theinvention; FIG. 2 is an enlarged fragmentary longitudinal sectional viewof the structure illustrated in FIG. 1;

FIG. 3 is a perspective view of a modified form of the DESCRIPTION OFTHE PREFERRED EMBODIMENTS Referring now to the drawings in detail,wherein like reference characters indicate like parts throughout theseveral figures, the reference numeral 10 indicates generally a safetytrailer hitch constructed in accordance with the invention.

The safety trailer hitch 10 includes a bar 11 attached to a towingvehicle (not shown) and having a ball 12 secured to the outer endthereof by' means of a threaded shaft 13 extending through a bore 14 inthe bar 11 and a nut 15 which is threaded onto the threaded shaft 13 andclamps the ball 12 tightly to the bar 11.

A generally cylindrical trailer tongue 16 has a coupling 17 rigidlysecured to the forward end thereof. The coupling 17 includes a socketportion 18 which is adapted to engage over the ball 12 and a pivotedclamp member 19 which is adapted to be clamped against the ball 12 bymeans of a bolt 20, hand wheel 21, and compression spring 22. The bolt20 extends upwardly through the clamp member 19 and through the top ofthe coupling 17 to receive the hand wheel 21 which is used to loosen ortighten the clamping member 19 under the ball 12. The ball 12 andcoupling 17 described above are conventional in construction and may beany conventional ball and coupling other than the specific couplingillustrated.

A bracket 23 is engaged over the bar 11 forwardly of the ball 12 and iswelded to the bar 11 at 241. A cylindrical boss 25 is welded at 26 tothe bracket 23 with a bolt 27 extending perpendicularly upwardlytherefrom. The boss 25 has a V shaped notch 28 formed in one sidethereof for reasons to be assigned.

A generally cylindrical member 29 has an axial bore 30 which is engagedover the bolt 27 and has a V shaped detent 31 in its lower face which isadapted to engage in the V shaped groove 28 of the boss 25. A finger 32extends radially outwardly from the member 29 terminating at a pointcentrally of the ball 12 overlying the socket 18 of the coupling 17. Awing nut 33 is threaded onto the bolt 27 to clamp the cylindrical member29 against the boss 25 with the detent 31 in the notch 28. With thecylindrical member 29 in this posi tion the finger 32 overlies thesocket 18 and will prevent the coupling 17 from becoming disengaged fromthe ball 12 should the clamp member 19 fail or become disengaged.

When coupling or uncoupling the hitch 10 the wing nut 33 is loosened andthe member 29 is rotated to move the finger 32 to a position away fromthe ball 12 to thus permit the coupling 17 to be disengaged from theball 12.

Referring now to FIGS. 3 through 5 a modified safety trailer hitch isindicated generally at 50. The trailer hitch 50 includes a channel towbar 51 secured to the towing vehicle (not shown). A ball 52 is securedto the tow bar 51 by means of a bolt 53 which extends therethrough and anut 54. A washer 55 is mounted beneath the ball 52 and has an annularflange 56 extending radially outwardly therefrom in spaced apartrelation with respect to the channel 51.

A housing generally indicated at 57 has a horizontal bottom wall 58which is provided with a central bore 59 to permit the bottom wall 58 topivot on the washer 55 while resting on the tow bar 51.

The bottom wall 58 of the housing 57 has a pair of upstanding side walls60, 61 integrally secured thereto and arranged in spaced apart generallyparallel relation. The side walls 60, 61 are connected by relatively lowfront and rear walls 62, 63 respectively to complete the housing.

A trailer tongue 64 is provided with a coupling 65 having a socket 66which is adapted to engage over the ball 52. A clamp member 67 isadapted to engage under the ball 52 in a conventional manner when thehand wheel 68 is adjusted on the coupling 65.

A U shaped yoke generally indicated at 69 has a leg 70 secured to theside wall 60 by a pivot bolt 71. A washer 72 is positioned between theleg 70 and the side wall 60 to permit the yoke 69 to swing freely. Theyoke 69 has a second leg 73 connected to the side wall 61 by means of apivot bolt 74. A washer 75 is positioned between the leg 73 and the sidewall 61 to permit the leg 73 to swing freely with respect thereto. A bar76 connects the legs 70, 73 as can be seen in FIG. 4.

The side wall 60 has an aperture 77 formed therein and the side wall 61has an aperture 78 formed therein. The apertures 77, 78 generallyoverlie the pivot bolts 71, 74. A spring arm 79 is secured to the leg 73by means of the pivot bolt 74 and a rivet 80 and carries a latch pin 81which extends through an aperture 82 in the leg 73 and is adapted toengage in the aperture 78 as illustrated in FIG. 4 to lock the yoke 69in an erect position with the bar 76 overlying the socket 66 to thusprevent the coupling 65 from becoming disengaged from the ball 52. Theupper end of the arm 79 is reverted at 83 to form a finger grip forpulling the arm 79 outwardly to release the latch pin 81 from theaperture 78 to permit the yoke 69 to be swung to a position out fromover top the ball 52 to permit the coupling 65 to be engaged anddisengaged at will.

The arm 79 is formed of spring material so that the latch pin 81 isnormally urged into seated engagement with the aperture 78.

Having thus described the preferred embodiments of the invention itshould be understood that numerous structural modifications andadaptations may be resorted to without departing from the spirit of theinvention.

What is claimed is:

1. In a safety trailer hitch of the type which includes a tow barmounted on the towing vehicle carrying a ball and a tongue mounted onthe trailing vehicle carrying a coupling for releasably clamping on theball, the improvement comprising a housing mounted on the tow bar andhaving the ball positioned therein, a U-shaped yoke secured to saidhousing at opposite ends thereof on a horizontally extending pivot forpivotal movement to a position overlying the coupling, and means forreleasably latching said yoke in its coupling overlying position toprevent the disengagement of the coupling from the ball.

2. A safety trailer hitch as claimed in claim 1, wherein the means forreleasably latching the yoke includes a spring pressed latch pin on saidyoke cooperating with an aperture in said housing to latch said yoke inerect position overlying said coupling.

3. A safety trailer hitch as claimed in claim 1, wherein said housing ispivotally mounted on the tow bar for rotation about a vertical axispassing through the ball to align said housing with said coupling.

a: v a: :t

1. In a safety trailer hitch of the type which includes a tow barmounted on the towing vehicle carrying a ball and a tongue mounted onthe trailing vehicle carrying a coupling for releasably clamping on theball, the improvement comprising a housing mounted on the tow bar andhaving the ball positioned therein, a U-shaped yoke secured to saidhousing at opposite ends thereof on a horizontally extending pivot forpivotal movement to a position overlying the coupling, and means forreleasably latching said yoke in its coupling overlying position toprevent the disengagement of the coupling from the ball.
 2. A safetytrailer hitch as claimed in claim 1, wherein the means for releasablylatching the yoke includes a spring pressed latch pin on said yokecooperating with an aperture in said housing to latch said yoke in erectposition overlying said coupling.
 3. A safety trailer hitch as claimedin claim 1, wherein said housing is pivotally mounted on the tow bar forrotation about a vertical axis passing through the ball to align saidhousing with said coupling.